Door-strike

A door opener for a door having a wing pivotally mounted to a door frame, said door opener comprising:

• a main body;
• a door opener latch hingedly mounted in the main body and pivotable between a closed position and an open position;
• a blocking member that is mounted in the main body and linearly displaceable from a locking position into a release position and back, the blocking member in its locking position forming a stop for the door opener latch in the closed position to prevent pivoting of the door opener latch into the open position, and the blocking member in its release position being so far offset from the door opener latch that the door opener latch may be pivoted from the closed position to the open position and back without any restriction of movement by the blocking member;
• and
• an actuator coupled with the blocking member for releasing or locking the door opener latch,
• wherein the actuator comprises a motor having a rotatable shaft supporting a worm thread, and a spring member having two end portions is provided, wherein a first end portion of the spring member comprises spring coils that directly engage with the worm thread in order to displace the spring member linearly in the direction of extension of the rotatable shaft by rotating the worm thread, and wherein a second end portion of the spring member is connected to the blocking member in order to displace the blocking member linearly in said direction of extension of the rotatable shaft from the locking position to the release position and back, and wherein the blocking member is decoupled from the actuator by the spring member arranged intermediate between the worm thread and the blocking member, wherein the spring member in the biased state serves as a store of energy with the spring force of the spring member in the biased state acting upon the blocking member to move the blocking member in the release position of the blocking member.